Pattern: Sliding Window (Arrays)

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Objective

Master the sliding window pattern and solve all problems from the RisingBrain DSA sheet.

References

• Course section: https://www.youtube.com/watch?v=Z_c4byLrNBU&t=1608s (0:26:48)
• Sheet: https://www.risingbrain.org/sheet#array
• Parent course ticket: DSA Patterns course - AlgoMonster / freeCodeCamp #2

Pattern Description

Maintain a window of fixed or variable size. Expand the right pointer, shrink the left pointer when a constraint is violated. Avoids nested loops by reusing computation from the previous window.

• Fixed size: window length k, slide across (max sum, distinct elements)
• Variable size: expand/shrink to satisfy a condition (longest substring, minimum subarray)

Nedbank VAS Relevance

Q70 (Optimizing Resource Allocation): fixed-size window of length k, all elements unique, return max sum.

Sub-issues

#	Problem	Difficulty
1	Maximum Sum Subarray of Size K	Easy
2	Max Consecutive Ones	Easy
3	Max Consecutive Ones III	Medium
4	Subarray Product Less Than K	Medium
5	Fruits Into Baskets	Medium
6	Minimum Size Subarray Sum	Medium
7	Sliding Window Maximum	Hard
8	Subarray with K Distinct Integers	Hard

Notes

Language: Java